PRESCRIBED BURNS
WHAT IS A PRESCRIBED BURN?
A prescribed burn, involves setting planned fires to maintain the health of a forest.
Prescribed burns are carried out under very controlled conditions and the day of a burn depends on many factors:
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wind speed
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wind direction
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temperature
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relative humidity
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ground fuel moisture
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and venting
The process for deciding the right day to light a fire begins months before the event.
We first look at an area and consider how smoke drift will evolve both below and above ridge top elevations and how that drift will behave given large scale weather patterns.
We identify weather patterns under which we should not light a prescribed burn to avoid putting too much smoke into the local air shed.
On the days leading up to the burn local weather experts forecast weather to calculate the fuel moisture and then the zone staff can use that to determine whether the fuels are dry enough but not too dry to safely meet the objectives of the burn.
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On the day a prescribed burn is to be lit, BC Wildfire Services are given a spot forecast for the exact location of the burn so they are aware of any large weather events coming up and avoid lighting the fire if for example a large wind event is heading in the direction of the burn or the smoke drift may be pushed in an undesirable direction.
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Materials burned in a planned fire include dead grass, fallen tree branches, dead trees, and thick undergrowth.
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Before a controlled burn is lit, a plan—or prescription—is drawn up. This plan includes details on how big the fire will be, what it will burn, and what managers hope to accomplish with the fire. It also includes the weather and environmental conditions under which the fire will burn and any situations that might require the fire to be extinguished.
Controlled-burn managers also map out how the fire will be set, how the smoke will be managed, how to inform the public, what protective equipment might be needed, and what firefighting resources should be standing by.
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Controlled burns are lit for a number of reasons. By ridding a forest of dead leaves, tree limbs, and other debris, a prescribed burn can help prevent a destructive wildfire. Controlled burns can also reduce insect populations and destroy invasive plants. In addition, fire can be rejuvenating. It returns nutrients to the soil in the ashes of vegetation that could otherwise take years to decompose. And after a fire, the additional sunlight and open space in a forest can help young trees and other plants start to grow.
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Some plants, such as certain pine species, require fire before the cones or fruits containing the seeds can release them. These cones or fruits need fire to melt a resin that holds the seeds inside. As a result, without fire these species cannot reproduce.
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Controlled burns have become more important as fire suppression efforts have grown over the last century. Historically, smaller fires occurred in forests at regular intervals. When these fires are suppressed, flammablematerials accumulate, insect infestations increase, forests become more crowded with trees and underbrush, and invasive plant species move in.
Controlled burns seek to accomplish the benefits that regular fires historically provided to an environment while also preventing the fires from burning out of control and threatening life and property."
THE HISTORY
OF PRESCRIBED FIRE
The use of prescribed fire by humans predates modern civilization in many areas worldwide.
Indigenous peoples have long used prescribed fire as an essential tool to manage wildlands for particular resources, such as desired plants and game species.
A number of indigenous peoples, including various North American tribes and Australian Aborigines, are known to have used fire to create favourable conditions for a variety of plants used for food, basketry materials, and clothing.
Prescribed fire has also been used to decrease the presence and abundance of pest species that can degrade the quality and quantity of desirable plants, as well as to clear land for village sites and to improve access and travel.
SIFCo 2018 WINLAW PRESCRIBED BURN
SIFCo 2022 PONDEROSA PRESCRIBED BURN
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Prescribed burning is one of a number of fuel management tools and techniques that can be used to help reduce the intensity of naturally occurring wildfires while returning an integral process to the ecosystem.
The Importance of Fire
Fire is a natural, normal process in many ecosystems and is necessary to maintain a healthy forest and the diversity of plant and animal life. Many plants and animals have not only adapted to fire but actually depend on it like the lodgepole pine which needs fire to help disperse its seeds. Naturally occurring fires also help to keep insects and disease under control by killing the pathogens infecting a stand. This is critical given that in recent years more than five times as much timber in B.C. has been lost to insects and disease than has been consumed by wildfire.
However, a history of aggressive and highly effective wildfire suppression in the Province has resulted in a significant build-up of forest fuels; greater tree encroachment on grasslands; and, ‘in-filling’ of once open, dry forests of the southern Interior and other areas. This has both increased the risk of devastating wildfires and negatively impacted biodiversity and forest health.
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Prescribed Fire
Prescribed fire is the planned and controlled application of fire to a specific land area and is one of the most ecologically appropriate and relatively efficient means for achieving planned public safety and resource management objectives, for example to enhance a habitat, prepare an area for tree planting or, for disease eradication.
Prescribed fire can also contribute to achieving air quality and climate action targets by preventing large, intense wildfires and replacing them with more frequent, well-timed, well-planned low-intensity fires.
These fires can take many months to plan and are managed in such a way as to minimize the chance of escape and emission of smoke while maximizing the benefits to the site.
NEW - FACTSHEET: Prescribed burns reduce wildfire risks (August 12, 2019)
Key objectives for the use of prescribed fire in British Columbia include:
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Creating and maintaining strategic fuel breaks both in the wildland-urban interface and the landscape,
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Reducing understory fuels, restoring fire maintained ecosystems,
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Improving wildlife habitat and domestic range, achieving reforestation objectives,
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Wildfire Act and Wildfire Regulation these are defined as resource management open fires.
Follow the link for more information on planning a burn.
Managed Wildfire
Managed wildfire is a type of prescribed burning. When a fire does not threaten people, property or other values, and could be of benefit to the natural ecosystem, managing it makes more sense than suppressing it.
The BC Wildfire Service supports planning for circumstances and situations where managed, low-risk wildfires are allowed to burn for the benefit of the ecosystem and under the close observation of wildfire management personnel. Planning for managed wildfire is a partnership between the BC Wildfire Service, Ministry of Environment and other land managers, and the general public who play a role in recognising of the importance of fire in BC's ecosystems.
When planning for managed wildfires, experts identify areas which are free of values at risk such as infrastructure, timber, or ecologically sensitive areas and which would benefit ecologically from fire. For example, in large parks and protected areas where the objective is to mimic natural disturbance patterns. The assessment and planning process for managed wildfires also includes fire growth projections and other modeling and helps to ensure that burning is facilitated under appropriate fire weather indices and conditions.